Virtual Wires: Overcoming Pin Limitations in FPGA-based Logic Emulators

Abstract

Existing FPGA-based logic emulators suffer from limited inter-chip communication bandwidth, resulting in low gate utilization (10 20 percent). This resource imbalance increases the number of chips needed to emulate a particular logic design and thereby decreases emulation speed, since signals must cross more chip boundaries. Current emulators only use a fraction of potential communication bandwidth because they dedicate each FPGA pin (physical wire) to a single emulated signal (logical wire). These logical wires are not active simultaneously are only switched at emulation clock speeds.